1. Field of the Invention
Embodiments of the present invention generally relate to navigation techniques and, more particularly, to a method and apparatus for generating three-dimensional pose using multi-modal sensor fusion.
2. Description of the Related Art
Real-time navigation systems generally rely upon Global Positioning System (GPS) receivers to provide position information. Such systems, by their reliance on satellite signals, are impaired when operating indoors. In an effort to overcome this impairment, multiple sensors for providing navigation information when GPS signals are unavailable have been developed. Real-time tracking by fusing information available from visual and inertial sensors (e.g., an inertial measurement unit (IMU)) has been studied for many years with numerous applications in robotics, vehicle navigation and augmented reality. However, it is still unclear how to best combine the information from these complementary sensors. Since inertial sensors are suited for handling situations where vision is lost due to fast motion or occlusion, many researchers use inertial data as backup or take only partial information (gyroscopes) from an IMU to support vision-based tracking systems.
To better exploit inertial data, several researchers use an extended Kalman filter to fuse all measurements uniformly to a pose estimate. These systems combine the filter with vision-tracking techniques based on artificial markers, feature points, or lines. Results from these Kalman filter-based systems indicate that using vision measurements effectively reduce the errors accumulated from IMU. However, these systems have not eliminated the problem of long-term drift over large areas inherent in an inertial-based navigation system.
Therefore, there is a need in the art for improved navigation using a method and apparatus for generating three-dimensional pose using multi-modal sensor fusion.